To insert JSON into a message I simply do that as a string, so no magic here. However I noticed that you need to structure it in a efficient way and also provide the model with some guidance about the data structure. You can have a look here how I implemented it on GitHub: nicolaszimmer/json-compact I’m processing health and activity data for analysis and it works pretty well, although GPT-4 is much better at complex queries and code interpreter is a big plus.